StructureSelector: A web-based software to select and visualize the optimal number of clusters using multiple methods.

Inferences of population genetic structure are of great importance to the fields of ecology and evolutionary biology. The program structure has been widely used to infer population genetic structure. However, previous studies demonstrated that uneven sampling often leads to wrong inferences on hierarchical structure. The most widely used ΔK method tends to identify the uppermost hierarchy of population structure. Recently, four alternative statistics (medmedk, medmeak, maxmedk and maxmeak) were proposed, which appear to be more accurate than the previously used methods for both even and uneven sampling data. However, the lack of easy-to-use software limits the use of these appealing new estimators. Here, we developed a web-based user-friendly software structureselector to calculate the four appealing alternative statistics together with the commonly used Ln Pr(X|K) and ΔK statistics. structureselector accepts the result files of structure, admixture or faststructure as input files. It reports the "best" K for each estimator, and the results are available as HTML or tab separated tables. The program can also generate graphical representations for specific K, which can be easily downloaded from the server. The software is freely available at http://lmme.qdio.ac.cn/StructureSelector/.